Fashionable style of art with peculiar lack of taste (9)
I believe the answer is:
indecorum
'lack of taste' is the definition.
'indecorum' can be an answer for 'taste' (I have seen 'bad taste' mean 'indecorum' so perhaps 'taste' could also mean 'indecorum'). I am unsure of the 'lack of' bit.
'fashionable style of art with peculiar' is the wordplay.
'fashionable' becomes 'in' (in can mean fashionable or trendy).
'style of art' becomes 'deco' (I've seen this in other clues).
'with' says to put letters next to each other.
'peculiar' becomes 'rum' (synonyms).
'in'+'deco'+'rum'='INDECORUM'
Can you help me to learn more?
(Other definitions for indecorum that I've seen before include "Improper behaviour" , "Bad behaviour" , "Lack of propriety" , "lack of decency!" , "Naughty behaviour" .)